trail_monkey

I'm redoing an old Panasonic touring model to give my wife an upright cruiser bike. I removed the free wheel cranks and discarded them and put a square taper bottom bracket in. Originally this bike was a 1x5. Now all I have are double cranks but they won't have a bash guard like the originals did to keep the chain from falling off the inside. I may turn this into a single speed for her but if I decide to keep the gears I'd really like to leave a single ring in the front. As it is when she rides a geared bike she won't shift anyways she's too stubborn lol. But her knees are getting worse and I want her to have some options. Can you buy inner and outer bash guards for 110 bcd vintage cranks? And also can you buy a thumby shifter that would shift a five or six speed indexed? This bike originally had a friction shifter mounted to the right side of the quill stem and she won't like that.

bikemig 

If you're going to stick to 120 OLD on the back, hunt around for a friction thumb shifter. Sunrace makes a nice one or look for something used. If you plan on spreading the frame to 126 OLD, you might as well go to 7 in the back. That way you can find a shimano 7 speed thumbshifter. Shimano makes some new stuff for flat bars that indexes with 7. Also check out what Sunrace and microshift have to offer. Keep in mind supply chains are busted due to Covid and trade wars so who knows what you'll find new.

The sun race friction thumb shifters aren't bad and they're a deal since they come with cables and housing for around $13:
https://www.modernbike.com/product-2...xoCR_sQAvD_BwE

I just installed a set on an old Rockhopper I built for my nephew. They're pretty decent.

You really don't need a bash guard for just riding on roads. Plus you really don't need one on the inside. Just adjust the front derailleur properly and you won't lose the chain. If you're worried about dropping the chain off to the inside, look around for a chain catcher like one of these

https://www.modernbike.com/product-2...hoC1DoQAvD_BwE

trail_monkey

I'm not planning on mounting the front derailleur. Of course it didn't have one but I've got plenty available from other vintage teardowns. It crossed my mind but I think I'm going to not put one on. Single speed is an option too. so hanging on my pegboard I have a 6-speed freewheel and a 7-speed freewheel. I forgot about the old standards but you just refreshed my memory. Is the 6-speed freewheel going to be The 120 and the 7 speed going to be the 126?

chainwhip

...does it roughly match something she already rides comfortably ?

bikemig 

5 speed freewheel works with 120 OLD; 6 or 7 with 126 OLD. They also used to make 6 speed freewheels that would fit on 120 OLD wheel but you likely don't have one of those.

You likely want to mount a front derailleur even if you are going with only one ring up front as that will help keep the chain from jumping off the chainring. That is most likely to happen when you are trying to take off before that light changes . . . .

trail_monkey

She's 5'10. I'm 6 ft. So she would be a little lower on the saddle than me but we're close. She doesn't have anything that she particularly rides. I gave her an old jamis mountain bike a few years ago and set it up with a short high-rise stem and Jones h bars to try to get her upright. And then I put 42 panaracer urban tires on. Even though it's a fairly upright bike she is still leaning forward and her joints bother her on rides. So I set out to build her a cruiser style. She's never going to ride anything like I do which is extremely hilly and technical at times. I just want to get her on something that she's willing to go to the city and ride the urban trails with me sometime so we can spend quality time together. It's been over a year since she's even been on the bike. I guess the answer to your question before I got off topic was yeah this frame should be fitting her pretty good. I had to raise a saddle up quite a bit to get the proper knee bend for myself.

barnfind

Not sure what your calling a 'Bash Guard'?

You shouldn't need anything up front besides a sprocket for the chain. Without a derailleur, with proper chain alignment, the chain doesn't need anything to stay on the sprocket.
A problem you may encounter is getting the correct chainline using just one of the double chain ring's sprockets.
Its often nessassary to add spacers and eliminate one ring to run it as a single speed front.
You can also look toward the BMX world of parts for a good single speed crankset.

What are your plans for the rear? Are you putting the freewheel back on or just going with a single speed BMX style freewheel?

If it were mine, I'd likely respoke the rear wheel to a three speed internal gear hub and find its original fenders.

They made that model in a 3 speed internal gear hub with a coaster brake, and both a 5 and a 10 speed derailleur model.

They were very similar to the Raleigh Sprite 27 and Schwinn Suburban models.

trail_monkey

I'm not sure what my plan is. My plan is to get her something to ride really cheap lol. I'm getting ready to switch jobs hopefully and on top of that she won't let me spend any money on a bike for her since she is not an avid rider. Fortunately I have a place nearby that has a bunch of old junk bikes laying around. most of them are cheap huffies from the '80s and other things but if you look hard enough you can find some of these old bikes that were worth a little bit at the time. I'm contemplating going single speed on the rear. I did that several years ago with a vintage bike and adjusted the axle spacers and redished the wheel to get the proper chain alignment and it worked very well. And that's probably the way she would like it to be honest with you because she is not a fan of shifting gears she just wants to get on the damn thing and ride. So the key is going to be finding the proper gear ratio that isn't bothering her knees. Since the only thing she'll ride with me are flat trails that at the most may have a two or three percent grade she isn't going to need many gears if any. I just don't want to set it up one way and then find out later I did something wrong for her. I'm trying to nail it right the first time lol

trail_monkey

What you see here is a picture of the original chainring. The chain ring and the integrated inner bash guard are pictured on the left splined onto the freewheel bottom bracket assembly. The outer bash guard is the shiny part on the right and it was held to the other two with five bolts. So this is what I was referring to. that kept the chain on the front ring while the rear did all the shifting

trail_monkey

I seen at least one bike over there today that had a 3.speed rear hub but I bet it was a 26" wheel. If the hub is worth snatching up I'd go get it by and lace it to the original rear hoop that was on this bike. I know nothing about 3 speed rear hubs so I don't know if this hub is a good one or a cheap one. I believe it was on a bike with ashbaugh cranks (did I pronounce that right?) So I assume it was a cheaper bike to begin with? I know I seen the linkage on the drive side of the hub.

JohnDThompson 

That's not a "bash guard," it's just a chain guard to help prevent your trousers from getting snagged on the chainring teeth. It looks like it's plastic, which would probably shatter if it actually "bashed" into something. True bash guards are only used on serious off-road bikes, where challenging surfaces may come in contact with the crank.

If you don't wear trousers with loose cuffs at the bottoms of the legs, or use a trouser clip of some sort if you do, there's really no need for a chainguard.

trail_monkey

I should have known that sorry..... But it is steel. It's part of the ring. I'm pretty sure they are machined together or riveted but not plastic for sure

trail_monkey

I googled a pic since mine has already been torn apart. Zoom in and you see the chain ring sandwiched between the inner and outer. Sorry I've been so misleading lol

JohnDThompson 

Ah, ok. If you're replacing that crank with a double, you won't need those chainguard pieces; the front derailleur will perform that function.

Prowler 

OP you said you two did not need to shift the front. OK but you could probably mount a FD then use the limit screws to lock it onto the ring you intend to use. No shifter nor cable. That would be easy and you could swap between the big ring and the small as her knees demand. No chainring guards needed. The cage on the FD would also discourage the chain from coming off your preferred ring. Unlikely but just leave it sit there.

trail_monkey

yeah that's what I'm thinking I might end up doing if I don't go single speed

barnfind

I don't see the need for any front derailleur if you going to shift the front sprockets.
I've owned dozens of 5 speed bikes with only a rear derailleur and they never needed anything to keep the chain on the front ring.
The tension of the derailleur should suffice in keeping the chain on the sprockets.

That inner ring appears to just be a product of cost cutting manufacturing. They did make a 10 speed version of that bike, so I suppose to save making two completely different stampings, they used the 10 speed stamping minus the process of cutting the teeth in it. It likely served to purposes, one to save making a second part, and second, it looks like it also serves as a means to attach the outer chainguard. If they had made a separate chain ring for the 5 speed model vs. the 10 speed, it would also likely have required making either a set of spacers for the same chainguard or making a special guard just for the 5 speed model.

Since you have the double chain ring already mounted up, and the wheel is dished for a five speed freewheel, why not just hang a front derailleur and make use of the double ring? All it would take is a shifter, cable and derailleur.

I suggested the internal gear hub because its what I would prefer on that kind of bike, it eliminates the need for an offset rear wheel, it simplifies the chain line issue and cleans up the whole bike in appearance. Not to mention they take very little maintenance.

The best 3 speed hub would be a Sturmey Archer AW model, but that bike would have come with a Shimano '333' three speed.
If you happen upon a Suntour three speed, those were clones of a Sturmey Archer hub and well worth using.

Shimano 3 speeds have a bad reputation for failing, although I've never run into one that failed under normal use under an average rider. Keep them lubed and they work just fine. If I were building a new wheel though, unless I was trying to be period correct or doing a restoration, I'd likely just use the Sturmey Archer hub.

ramzilla

Looks like one of those weird front freewheel system. I think they were called Shimano FFS or something. You definitely need to ditch that thing.

trail_monkey

I went rummaging again this afternoon and I found three Sturmey Archer rear hubs and probably seven shimanos. The problem is the Sturmey Archers were all seized up and junk. Several of the shimano's still actuate. I brought one of each home and tried to tear them down in my bench. The Shimano is the one that still greased inside and everything looks good. The Sturmey is seized up and rusted and in real bad shape. We're not dealing with a bike that is worth anything so to speak and I think I'm getting too far over my head trying to dump money into something that's not worth it. I'm going to focus on making it work with what I have available and not trying to build a new rear wheel. In fact I'm actually thinking about going single speed as she will only be riding this on really easy trails anyways.

trail_monkey

Yeah I read about those lol and that's exactly what it is. It's already been hauled away with the trash this morning. Sheldon Brown called that a solution looking for a problem. I can understand why. My God as easy as it was to construct a rear freewheel why in the heck would they try to integrate it with the bottom bracket lol?

dedhed

https://www.treefortbikes.com/cat/1325/Chainring-Guards

barnfind

Sturmey Archer hubs are easier to fix, the best fix for a Shimano is a complete cartridge insert, its not worth dealing with overhauling one that's rusted up and seized, regardless of the brand.
You could certainly just toss on a BMX freewheel and leave it at that, then if she likes riding the bike, then add some gears later.
I wouldn't get into tearing apart the Shimano, if its not broke, don't fix it, make sure its got lube, and built it into a suitable wheel. It shouldn't be hard to find a good used 27" rim to build it into.

trail_monkey

Yeah there's plenty of used rims over there.

rootesgroup

I have a problem acquiring vintage parts and it goes like this...

I search for a parts bike that is inexpensive and I find one for $20-25. I bring it home and look it over. Then I decide that the bike is too nice or too interesting to part out and I decide to fix it. So, now I have another bike and I still need parts... even more so now.

The last two bikes that I got this way were a 73 Raleigh step-thru LTD-3 and a 1960 Western Flyer English made 3 speed. The LTD-3 turned out to be completely original, even having the pedals with the 'R' in them. The Western Flyer has a Sturmey 3 speed hub with coaster brake (a first for me) and is also original.

Man, I have to find some parts bikes that are not worth fixing.

Hudson308 

If you decide you still want to use a single chainring up front and a derailleur in back, and you're still worried about dropping the chain up front, you can use what's called a narrow-wide chain ring. These have alternating width teeth, designed to retain the chain better than typical chainring teeth. You normally wouldn't need one unless you use more than 7 cogs out back, as the chain deflection increases with those wider cassettes. They may also help with 6- or 7-speeds when you can't get optimal chain line with the parts on hand.